1. Field of the Invention
Exemplary aspects of the present invention generally relate to an image forming apparatus including a fixing device that fixes an image onto a recording medium.
2. Description of the Background
Related-art image forming apparatuses, such as copiers, printers, facsimile machines, and multifunction devices having two or more of copying, printing, and facsimile functions, typically form a toner image on a recording medium (e.g., a sheet of paper, etc.) according to image data using an electrophotographic method. In such a method, for example, a charger charges a surface of an image carrier (e.g., a photoconductor); an irradiating device emits a light beam onto the charged surface of the photoconductor to form an electrostatic latent image on the photoconductor according to the image data; a developing device develops the electrostatic latent image with a developer (e.g., toner) to form a toner image on the photoconductor; a transfer device transfers the toner image formed on the photoconductor onto a sheet of recording media; a cleaning device removes residual toner from the surface of the photoconductor, and a fixing device applies heat and pressure to the sheet bearing the toner image to fix the toner image onto the sheet. The sheet bearing the fixed toner image is then discharged from the image forming apparatus.
In the fixing device, a fixing member heated by a heat source and an opposing member (or a pressing member) provided opposite the fixing member contact each other to form a fixing nip therebetween. Heat and pressure are applied to the sheet while the sheet is passing through the fixing nip so as to fix the toner image onto the sheet.
The heat generated by the fixing device can cause internal problems for the image forming apparatus. For this reason, an exhaust fan or a cooling fan is often provided near the fixing device so as to forcibly exhaust the heat generated from the fixing device to the outside, thereby preventing the heat from the fixing device from adversely affecting operation or performance of components or devices of the image forming apparatus provided near the fixing device.
However, provision of the exhaust fan increases both size and production costs of the image forming apparatus, and moreover the exhaust fan can be noisy.
Accordingly, an image forming apparatus in which the heat generated by the fixing device is released to the outside without using an exhaust fan has been proposed. Specifically, the fixing device is disposed in an upper separate portion of the image forming apparatus, and the heat generated from the fixing device is exhausted from a first air vent to the outside. At the same time, the tendency of heat to rise is utilized to draw outside air from a second air vent to cool the fixing device. However, such a configuration increases the height of the image forming apparatus, and is not suitable for a tandem-type compact image forming apparatus.